A discovery made by Russian Cosmonauts aboard the International Space Station has experts around the world paying close attention—they've announced they've found some form of living bacteria that exists in the vacuum of space.

The bacteria were found on the outer hull of the ISS, and definitely were not there when the station originally launched, all the way back in 1998. Naturally, this has led to questions about where they could have come from.

Samples of the bacteria have been collected on cotton swabs, and tested to ensure that they don't pose any kind of danger to life on Earth.

The samples will be transported home during an upcoming supply run, where scientists will be able to study them in greater detail to be able to determine exactly what they are, and how they got on the outside of the ISS.

"It turns out that somehow these swabs reveal bacteria that were absent during the launch of the ISS module. That is, they have come from outer space and settled along the external surface. They are being studied so far and it seems that they pose no danger."

While Shkaplerov sounds convinced that these bacteria came from outer space, it's probably worthwhile remain skeptical about the true origin of these micro-organisms.

The idea of alien bacteria floating through space and getting stuck on the side of the ISS might sound very romantic and exciting, but it's probably not the most likely explanation.

As we haven't seen any other proof of space bacteria at present, it's probably the case that these creatures found on the ISS hull were the result of contamination from inside the station itself, which, naturally, is swarming with earth life.

Any time an astronaut takes something outside with them on a space walk to adjust experiments or perform maintenance, there's a chance that bacteria could be carried out of the station, leaving them free to attach themselves to the outer side of the hull.

Nevertheless, while it's entirely possible that these bacteria aren't actually alien life forms, their existence is exciting in and of itself.

Even if these prove to be terrestrial in nature, there's a lot that scientists can learn about the conditions of space from studying the bacteria up close, which may help us to understand the kinds of alien life we might discover at some point in the future.

Besides, this discovery definitely proves the existence of bacteria in outer space, even if they are of our own accidental creation. If bacteria can end up on the ISS hull, there's nothing to stop tiny microscopic creatures from living quite comfortably as they float endlessly in space.

We might not have found incontrovertible proof of alien life just yet, but we might have launched creatures off to other far-flung worlds by accident, and that's interesting in and of itself.